Study On Quality Control Technology Of Fresh-cut Vegetables----Fresh-cut Potato And Lotus Root

This study used potato (Solanum tuberosum L.) and lotus root (Nelumbo nucifera Gaertn.) as the tests material, study the quality control technology-Rinsing, Color-protecting, Packaing and fresh-cut technics. The physiological and biochemical indexes such as the PPO activity, malondialdehyde (MDA) content, respiration rate; the sensory quality indexes such as the color difference, weight loss rate, browning degree and the security indexs such as total bactericum count were determined to provide theoretical basis and technical reference for fresh-cut vegetables processing and production. Research methods and main conclusion are as follows:1. The efficacy of different sanitizers on fresh-cut potato and lotus root at4℃was investigated. Results show that as a new sanitizer, acid electrolysis of water for fresh-cut potato sterilization effect is best, and can effectively maintain its appearance quality, inhibiting browning, reduce the activity of PPO and the weight loss rate, keep fresh-cut lotus root color difference and overall sensory quality, effectively inhibit the occurrence of browning, reduce the PPO activity and the weightlessness rate, keep the content of polyphenols, delay the accumulation of MDA, effectively prolong the shelf-life of fresh-cut lotus root.2. The ascorbic acid, citric acid, L-cysteine was used alone to control browning of fresh-cut potato, browning degree as the detection index. The result indicated that the effect of control browning is ascorbic acid> L-Cys> citric acid. It is concluded that the reagent untited with0.1%ascorbic acid+0.5%citric acid+0.1%L-cysteine has a best effect on control browning by orthogonal test and verification experiments; and the shelf-life of fresh-cut potato can reach7d.3. The ascorbic acid, cysteine, kojic acid, and phytic acid was used alone to control browning of fresh-cut lotus root, the browning degree, color difference and soluble solids content were determined, the results showed that the reagent untited with0.5%ascorbic acid+0.1%cysteine+0.05%kojic acid+0.2%phytic acid has a best effect on control browning by orthogonal test and verification experiments; and the shelf-life of fresh-cut lotus root can reach12-14d.4. The efficacy of different permeability of packaging materials in improving the storage quality on fresh-cut potato and lotus root was investigated. The results showed that the commercialization of PE2packaging is more advantageous than other packing materials delay the fresh-cut potato and lotus root malignant change in the quality of colour and lustre, at the same time PE2can slow down the accumulation of MDA, inhibiting browning and respiratory rate, and slow the aging, improve the storage quality, prolong the shelf-life.5. The viable processing technical for fresh-cut potato obtains by this study is as follows:The fresh potatoâ†'picking and sortingâ†'cleaningâ†'shreding (10cm×0.3cm×0.3cm)â†'cleaning with acidic electrolyzed water (pH2.51, ACC60mL/L, ORP1140mV) for10minâ†'rinsingâ†'browning cotrolling with0.1%ascorbic acid+0.5%citric acid+0.1%L-cysteine for15minâ†'centrifugal dehydrationâ†'packaing with PE2(thickness:32μm, water vapor transmission rate:1.632g·m·(m2·d)-1, oxygen transmission rate:2743.579cm3·(m2·24h·0.1MPa)-1,carbon dioxide transmission rate:13927.765cm3·(m2·24h·0.1MPa)-1)â†'stored under4℃.6. The viable processing technical for fresh-cut lotus root obtains by this study is as follows:The fresh lotus rootâ†'picking and sortingâ†'cleaningâ†'slicing (4-5mm)â†'leaning with slightly acidic electrolyzed water (pH5.65, ACC48mL/L, ORP800mV) for10minâ†'rinsingâ†'browning cotrolling with0.5%ascorbic acid+0.1%cysteine+0.05%kojic acid+0.2%phytic acid for15minâ†'centrifugal dehydrationâ†'packaing with PE2(thickness:32μn, water vapor transmission rate:1.632g·m·(m2·d)-1, oxygen transmission rate:2743.579cm3·(m2·24h·0.1MPa)-1, carbon dioxide transmission rate:13927.765cm3·(m2·24h·0.1MPa)-1)â†'stored under4℃.